In considering a general method for the interaction of shear and compression buckling several parameters need to be reviewed or considered:
- Will the same interaction hold for interaction of elastic and plastic buckling effects?
- Will the same interaction hold for simply supported panel edges and clamped edges?
- Will the same interaction hold for all panel aspect ratios?
- Will the same interaction hold for flat and curved panels?
- As the presence of tension assists resistance to shear buckling is there a way to account for the buckling interaction in the positive axial load domain as well?
(NACA-TN-3184, 1954) refers to the references (NACA-WR-3K13, 1943) and (NACA-TN-1990, 1949) which have the derivations for the elastic and plastic interaction curves. From a review of these references it can be seen that the elastic interaction is conservative compared to the plastic interaction. Therefore, the elastic interaction can be used for both elastic and plastic buckling interactions.
This interaction is described by the following equation:
As the methods in (NACA-TN-2661, 1952) are generally applicable to panels with all edge restraints it is reasonable to assume this interaction is likewise applicable. This interaction is in agreement with the interaction for a flat panel in (NACA-WR-3K13, 1943).
(NACA-TN-1223, 1947) gives both the extension into the positive axial load domain and a comparison of shear and compression buckling interaction for panels of different aspect ratios for panels loaded along the long edge and the short edge in compression.
A review of all of these references shows that for flat and curved panels, with simply supported or clamped edge restraint, for any aspect ratio, loaded in compression along the short or the long edge and applicable in the tension end load domain the following interaction is appropriate and/or conservative:
This function is graphed in the following figure:
A spreadsheet with this curve and a plotted margin of safety calculation is available here: